diff --git a/ui/index.html b/ui/index.html
index 1872b4fb..e064d24a 100644
--- a/ui/index.html
+++ b/ui/index.html
@@ -289,13 +289,13 @@
 </div>
 </body>
 
-<script src="media/js/parameters.js?v=3"></script>
+<script src="media/js/parameters.js?v=4"></script>
 <script src="media/js/plugins.js?v=1"></script>
 <script src="media/js/utils.js?v=6"></script>
 <script src="media/js/inpainting-editor.js?v=1"></script>
 <script src="media/js/image-modifiers.js?v=6"></script>
-<script src="media/js/auto-save.js?v=6"></script>
-<script src="media/js/main.js?v=9"></script>
+<script src="media/js/auto-save.js?v=7"></script>
+<script src="media/js/main.js?v=10"></script>
 <script src="media/js/themes.js?v=4"></script>
 <script src="media/js/dnd.js?v=8"></script>
 <script>
@@ -306,6 +306,7 @@ async function init() {
     await getAppConfig()
     await loadModifiers()
     await loadUIPlugins()
+    await getDevices()
 
     setInterval(healthCheck, HEALTH_PING_INTERVAL * 1000)
     healthCheck()
diff --git a/ui/media/js/auto-save.js b/ui/media/js/auto-save.js
index 5fec8433..da4dd5ad 100644
--- a/ui/media/js/auto-save.js
+++ b/ui/media/js/auto-save.js
@@ -34,7 +34,6 @@ const SETTINGS_IDS_LIST = [
     "diskPath",
     "sound_toggle",
     "turbo",
-    "use_cpu",
     "use_full_precision",
     "auto_save_settings"
 ]
diff --git a/ui/media/js/main.js b/ui/media/js/main.js
index fac0be99..047b1dd3 100644
--- a/ui/media/js/main.js
+++ b/ui/media/js/main.js
@@ -1,6 +1,7 @@
 "use strict" // Opt in to a restricted variant of JavaScript
 const HEALTH_PING_INTERVAL = 5 // seconds
 const MAX_INIT_IMAGE_DIMENSION = 768
+const MIN_GPUS_TO_SHOW_SELECTION = 1
 
 const IMAGE_REGEX = new RegExp('data:image/[A-Za-z]+;base64')
 
@@ -26,6 +27,7 @@ let maskImageSelector = document.querySelector("#mask")
 let maskImagePreview = document.querySelector("#mask_preview")
 let turboField = document.querySelector('#turbo')
 let useCPUField = document.querySelector('#use_cpu')
+let useGPUsField = document.querySelector('#use_gpus')
 let useFullPrecisionField = document.querySelector('#use_full_precision')
 let saveToDiskField = document.querySelector('#save_to_disk')
 let diskPathField = document.querySelector('#diskPath')
@@ -771,7 +773,7 @@ function getCurrentUserRequest() {
             height: heightField.value,
             // allow_nsfw: allowNSFWField.checked,
             turbo: turboField.checked,
-            use_cpu: useCPUField.checked,
+            render_device: getCurrentRenderDeviceSelection(),
             use_full_precision: useFullPrecisionField.checked,
             use_stable_diffusion_model: stableDiffusionModelField.value,
             use_vae_model: vaeModelField.value,
@@ -807,6 +809,14 @@ function getCurrentUserRequest() {
     return newTask
 }
 
+function getCurrentRenderDeviceSelection() {
+    if (useCPUField.checked) {
+        return 'cpu'
+    }
+
+    return $(useGPUsField).val().join(',')
+}
+
 function makeImage() {
     if (!isServerAvailable()) {
         alert('The server is not available.')
@@ -1113,6 +1123,15 @@ promptStrengthSlider.addEventListener('input', updatePromptStrength)
 promptStrengthField.addEventListener('input', updatePromptStrengthSlider)
 updatePromptStrength()
 
+useCPUField.addEventListener('click', function() {
+    let gpuSettingEntry = getParameterSettingsEntry('use_gpus')
+    if (this.checked) {
+        gpuSettingEntry.style.display = 'none'
+    } else if ($(useGPUsField).val().length >= MIN_GPUS_TO_SHOW_SELECTION) {
+        gpuSettingEntry.style.display = ''
+    }
+})
+
 async function changeAppConfig(configDelta) {
     // if (!isServerAvailable()) {
     //     // logError('The server is still starting up..')
@@ -1314,6 +1333,43 @@ async function getDiskPath() {
     }
 }
 
+async function getDevices() {
+    try {
+        let res = await fetch('/get/devices')
+        if (res.status === 200) {
+            res = await res.json()
+
+            let allDeviceIds = Object.keys(res['all']).filter(d => d !== 'cpu')
+            let activeDeviceIds = Object.keys(res['active']).filter(d => d !== 'cpu')
+
+            if (activeDeviceIds.length === 0) {
+                useCPUField.checked = true
+            }
+
+            if (allDeviceIds.length < MIN_GPUS_TO_SHOW_SELECTION) {
+                let gpuSettingEntry = getParameterSettingsEntry('use_gpus')
+                gpuSettingEntry.style.display = 'none'
+
+                if (allDeviceIds.length === 0) {
+                    useCPUField.checked = true
+                    useCPUField.disabled = true // no compatible GPUs, so make the CPU mandatory
+                }
+            }
+
+            useGPUsField.innerHTML = ''
+
+            allDeviceIds.forEach(device => {
+                let deviceName = res['all'][device]
+                let selected = (activeDeviceIds.includes(device) ? 'selected' : '')
+                let deviceOption = `<option value="${device}" ${selected}>${deviceName}</option>`
+                useGPUsField.insertAdjacentHTML('beforeend', deviceOption)
+            })
+        }
+    } catch (e) {
+        console.log('error fetching devices', e)
+    }
+}
+
 
 /* setup popup handlers */
 document.querySelectorAll('.popup').forEach(popup => {
diff --git a/ui/media/js/parameters.js b/ui/media/js/parameters.js
index 0e541cd7..2e270d9c 100644
--- a/ui/media/js/parameters.js
+++ b/ui/media/js/parameters.js
@@ -8,6 +8,7 @@
  var ParameterType = {
     checkbox: "checkbox",
 	select: "select",
+	select_multiple: "select_multiple",
 	custom: "custom",
 };
 
@@ -72,6 +73,13 @@ var PARAMETERS = [
 		note: "warning: this will be *very* slow",
 		default: false,
 	},
+	{
+		id: "use_gpus",
+		type: ParameterType.select_multiple,
+		label: "GPUs to use",
+		note: "select multiple GPUs to process in parallel",
+		default: false,
+	},
 	{
 		id: "use_full_precision",
 		type: ParameterType.checkbox,
@@ -95,6 +103,13 @@ var PARAMETERS = [
 	},
 ];
 
+function getParameterSettingsEntry(id) {
+	let parameter = PARAMETERS.filter(p => p.id === id)
+	if (parameter.length === 0) {
+		return
+	}
+	return parameter[0].settingsEntry
+}
 
 function getParameterElement(parameter) {
 	switch (parameter.type) {
@@ -102,8 +117,10 @@ function getParameterElement(parameter) {
 			var is_checked = parameter.default ? " checked" : "";
 			return `<input id="${parameter.id}" name="${parameter.id}"${is_checked} type="checkbox">`
 		case ParameterType.select:
+		case ParameterType.select_multiple:
 			var options = (parameter.options || []).map(option => `<option value="${option.value}">${option.label}</option>`).join("")
-			return `<select id="${parameter.id}" name="${parameter.id}">${options}</select>`
+			var multiple = (parameter.type == ParameterType.select_multiple ? 'multiple' : '')
+			return `<select id="${parameter.id}" name="${parameter.id}" ${multiple}>${options}</select>`
 		case ParameterType.custom:
 			return parameter.render(parameter)
 		default:
@@ -118,10 +135,12 @@ function initParameters() {
 	PARAMETERS.forEach(parameter => {
 		var element = getParameterElement(parameter)
 		var note = parameter.note ? `<small>${parameter.note}</small>` : "";
-		var newrow = `<tr>
+		var newrow = document.createElement('tr')
+		newrow.innerHTML = `
 			<td><label for="${parameter.id}">${parameter.label}</label></td>
-			<td><div>${element}${note}<div></td></tr>`
-		parametersTable.insertAdjacentHTML("beforeend", newrow)
+			<td><div>${element}${note}<div></td>`
+		parametersTable.appendChild(newrow)
+		parameter.settingsEntry = newrow
 	})
 }
 
diff --git a/ui/sd_internal/task_manager.py b/ui/sd_internal/task_manager.py
index 7fd7aba2..b11ffd68 100644
--- a/ui/sd_internal/task_manager.py
+++ b/ui/sd_internal/task_manager.py
@@ -9,11 +9,12 @@ import traceback
 
 TASK_TTL = 15 * 60 # seconds, Discard last session's task timeout
 
+import torch
 import queue, threading, time, weakref
 from typing import Any, Generator, Hashable, Optional, Union
 
 from pydantic import BaseModel
-from sd_internal import Request, Response
+from sd_internal import Request, Response, runtime
 
 THREAD_NAME_PREFIX = 'Runtime-Render/'
 ERR_LOCK_FAILED = ' failed to acquire lock within timeout.'
@@ -356,20 +357,36 @@ def get_cached_task(session_id:str, update_ttl:bool=False):
     return task_cache.tryGet(session_id)
 
 def get_devices():
+    devices = {
+        'all': {},
+        'active': {},
+    }
+
+    # list the compatible devices
+    gpu_count = torch.cuda.device_count()
+    for device in range(gpu_count):
+        if runtime.device_would_fail(device):
+            continue
+
+        devices['all'].update({device: torch.cuda.get_device_name(device)})
+
+    devices['all'].update({'cpu': runtime.get_processor_name()})
+
+    # list the activated devices
     if not manager_lock.acquire(blocking=True, timeout=LOCK_TIMEOUT): raise Exception('get_devices' + ERR_LOCK_FAILED)
     try:
-        device_dict = {}
         for rthread in render_threads:
             if not rthread.is_alive():
                 continue
             weak_data = weak_thread_data.get(rthread)
             if not weak_data or not 'device' in weak_data or not 'device_name' in weak_data:
                 continue
-            device_dict.update({weak_data['device']:weak_data['device_name']})
-        return device_dict
+            devices['active'].update({weak_data['device']: weak_data['device_name']})
     finally:
         manager_lock.release()
 
+    return devices
+
 def is_first_cuda_device(device):
     from . import runtime # When calling runtime from outside thread_render DO NOT USE thread specific attributes or functions.
     return runtime.is_first_cuda_device(device)
diff --git a/ui/server.py b/ui/server.py
index 43c20348..05225672 100644
--- a/ui/server.py
+++ b/ui/server.py
@@ -336,6 +336,8 @@ def render(req : task_manager.ImageRequest):
         print('WARNING Replace {use_cpu: true} by {render_device: "cpu"}')
         req.render_device = 'cpu'
         del req.use_cpu
+    if req.render_device != 'cpu':
+        req.render_device = int(req.render_device)
     if req.render_device and task_manager.is_alive(req.render_device) <= 0: raise HTTPException(status_code=403, detail=f'{req.render_device} rendering is not enabled in config.json or the thread has died...') # HTTP403 Forbidden
     if req.use_face_correction and task_manager.is_alive(0) <= 0: #TODO Remove when GFPGANer is fixed upstream.
         raise HTTPException(status_code=412, detail=f'GFPGANer only works GPU:0, use CUDA_VISIBLE_DEVICES if GFPGANer is needed on a specific GPU.') # HTTP412 Precondition Failed
@@ -437,7 +439,7 @@ if 'render_devices' in config:  # Start a new thread for each device.
         print('WARNING: No active render devices after loading config. Validate "render_devices" in config.json')
         print('Loading default render devices to replace invalid render_devices field from config', config['render_devices'])
 
-if task_manager.is_alive() <= 0: # Either no defauls or no devices after loading config.
+if task_manager.is_alive() <= 0: # Either no defaults or no devices after loading config.
     # Select best GPU device using free memory, if more than one device.
     if task_manager.start_render_thread('auto'): # Detect best device for renders
         # if cuda:0 is missing, another cuda device is better. try to start it...
@@ -455,7 +457,7 @@ if is_using_a_gpu and task_manager.is_alive(0) <= 0:
     print('Add the line "@set CUDA_VISIBLE_DEVICES=N" where N is the GPUs to use to config.bat')
     print('Add the line "CUDA_VISIBLE_DEVICES=N" where N is the GPUs to use to config.sh')
 
-print('active devices', task_manager.get_devices())
+# print('active devices', task_manager.get_devices())
 
 # start the browser ui
 import webbrowser; webbrowser.open('http://localhost:9000')